Belt guide



R. H. GRIFFIN Aug. 3, 1954 BELT GUI DE s Sheet-Sheet 1 Filed Maize, 1951Inventor: Robert, H. Griffin his Attorney Aug. 3, 1954 R. H. GRIFFI BELTGUIDE Filed May 29, 1951 v By V g u/m his Attorn y n .m a e .m m m G I.w H a t w R I WEE 4 A R. H. GRI/FFIN Aug. 3, 1954 BELT GUIDE Filed May29, 1951 3 Sheets-Sheet 3 FIG. 7

4 Inventor: Robert H. Griffin his Attorney Patented Aug. 3, 1954 UNITEDSTATES PATENT OFFIQ BELT GUIDE Robert H. Griifin, Yonkers, N. Y.,assignor to Tanners Research Corporation, New York N. Y., a corporationof Delaware Application May 29, 1951, Serial No. 228,910

-17 Claims. 1

This invention relates toguidesifor maintaining belts or like members inalignment axially of the rolls over which they'travel.

The primary object of'the invention is to provide an improved guide forbelts and the like employing feeler controlled actuated mechanism forautomatically resisting creepage.

Another object of the inventionis'to provide an improved guide for beltsand the like wherein a cam actuated control, responsive to anedgefeeler, automatically actuates mechanism by which a supporting rollis swung to overcome creepage.

An additional object of the invention is to provide a guide for beltsand the like having-a lost motion connection between an edge feeler anda'control valve whereby a fluid pressure cylinder actuated guide roll isenabled to reducecreepage to a minimum.

A further object of the invention is'to provide a guide for belts havinga pin and slot connection for camming 'a guide roll controlling valvetooperative position whereby a minimium creepage of a belt produces amaximum restoring force in the guide roll.

Another object of the invention is to provide a guide forbelts and thelike utilizing flui'd pressure for automatically actuating a guide roll,wherein the extent and sensitivity'of the alignmentrestoring force isreadily adjustable to control the extent of creepage.

Other objects and advantages of the invention will appear hereinafter inthe detailed description, be-particularly pointed out inthe appendedclaims, and illustrated in the "accompanying drawings in which:

Figure 1 is a front'elevationalview of a preferred form of the beltguide of the present invention;

Figure 2 is a vertical sectional view taken along the lines 22 of Figure1;

Figure 3 is afragmentary horizontal'sectional view taken along the lines3-3 ofFigure 1;

Figure 4 is a fragmentary vertical sectional view on an enlarged scale,taken along the lines 4-4 of Figure 1, with parts shown in elevationto-more clearly illustrate certain'of the details of construction;

Figure 5 is a'vertical sectional view taken along the lines 5-5 ofFigure 4;

"Figure 6 is a plan view 'of'the control mechanism of Figure 4;

Figure '7 is a horizontal sectional 'view taken alongthe lines l| ofFigure 5;' and "Figure'8is a schematic view showingthe relation betweenthe control valve andthe actuating cylinder.

Referring now in detail to the drawings 'in which like referencecharacters designate like parts, the improved guide of thepresent'invention is adapted to guide belts, strips and other members,which in traveling over one or more supporting rolls tend to creep ortrack out of alignment axially of the rolls, such members hereinafterbeing collectively termed belts. In the illustrated form of theinvention, the improved guide is comprised of a guideroll I over which abelt 2 travels. Depending upon its application, the guide roll I may beeither'a drive or an idler roll, the latter being preferred forsimplicity of construction and the r011 preferably being positioned toengage and support the belt intermediate fixed driving and driven rollsin the manner illustrated in-my copending application Serial No.159,436, filed May 2, 1950.

The guide roll I is suitably journaled in a yoke 3 surmounting orsupported by a support member 4 and connected thereto by a centerbearing 5, the center pin 6 of the bearing being positioned to enablethe guide roll to swivel or pivot horizontally about a central verticalaxis. The support member, in turn, may be supported on or between thesides 1 of a suitable frameto which its ends are attached by mountingbrackets 8.

For swiveling or pivoting the guide roll about its axis, there isprovided an air or other fluid pressure actuating cylinder 9 which mayconveniently be swivelly anchored to an outrigger l0 fixed to thesupport member 4 and has the free end of 4 its piston rod ll swivellyconnected to the base i2 of the yoke 3 adjacent one of its ends.

The control mechanism by which the actuating cylinder 9 is actuated toswivel the guide roll I is comprised of a pair of feelers I3, disposedon either side of or straddling the belt 2 and each engaging orcontacting an edge of the belt as it creeps to that side. To minimizefriction between the belt and the feelers, the latter are preferablyrollers rotatable about axes normal to the travel of the belt and eachmounted on a supporting block M. Both blocks are slidably mountedon acommon guide shaft or rod 55, one end of which is slidably orreciprocally received in a sleeve bearing 16 attached'to one of thesides I of the frame. The shaft l5 extends below and substantiallynormal or perpendicular to the path of travel of the belt 2 and isspacedfrom the guide roll I sufiiciently toprevent interference withswivellingof the latter. Thepositions of the feeler rollers 13 axiallyof the shaft [5 and therethrough their spacing laterally relative to theedges of the belt are made settable by set screws ll carried by theirsupporting blocks Hi.

The end of the shaft I5 opposite that received in the sleeve bearing I6is releasably fixed in an upper web it! of a cap member is by a taperpin 20, the cap member below its web, being bifurcated and having itsspaced legs 2| welded or otherwise fixed to the upper face of a cam orsliding plate 22 adjacent the opposite sides thereof. As shown, the camplate 22 is slidable or reciprocable between spaced side elements 23 ofa guide plate 2d, the cam and guide plates being interlocked againstother than such movement by beveling the edges 25 of the cam plate andcorrespondingly forming the confronting walls 26 of the guide plate.Sliding friction between the engaging surfaces of the cam and guideplates is preferably reduced by the provi sion of a pair of oilers 21each mounted on one of the side elements 23 of the guide plate 25 andconnected to a passage 28 leading through the associated element to theadjacent engaging surfaces of the plates. For fixing its position, theguide plate 24 is bolted to a base 29 attached to the adjacent of thesides I of the frame.

Also mounted on and shiftable or slidable rela tive to the base 29,normal to the path of movement of the cam plate 22, is a carriage 30.This carriage is formed of a pair of horizontally spaced end plates 3ijoined by veretically spaced connecting rods 32, each of which is guidedin a pair of horizontally spaced projections or lugs 33 outstanding fromthe base 28 the connecting rods being supported in the lugs in bushing3d of the self-lubricating type, which are held in place by retainers35.

For transferring movement of the cam plate 22 to the carriage 3B, thecam plate is slotted longitudinally to provide a cam slot 36, straddledby the legs 2! of the cap member 19 and having elongated relativelyoffset end portions 31 connected by a diagonally or angularly disposedor inclined central portion 38. Within this slot is adapted to slide orride a cam pin or bolt 39 which is secured to and upstanding from theupper edge of the underlying one of the end plates M of the carriage 38.To facilitate relative movement of the cam and end plates 22 and 3!, aroller or sleeve bearing 40 is interposed between the cam pin 39 and theedges of the cam slot 36 and fiat bearings 41 are inserted be tween theconfronting faces of cam and end plates and between the upper end of thesleeve 48 and a cotter pin 42 by which it is held in place.

With the cam plate 22 and the carriage so so connected, and the cam pin39 normally riding midway of the inclined central portion 38 of the camslot 35, movement of the cam plate on the application of force to theguide shaft it through one of the feeler rollers l3 will immediatelyshift the carriage 3d transversely of the cam plate. This shiftingcontinues until the cam pin 39 reaches one of the elongated end portions31 of the cam slot, whereafter the carriage will be held in its shiftedposition regardless of further outward movement of the cam pin,remaining in that position until the cam pin is returned to the centralportion 33 of the slot by corresponding movement of the guide shaft l5by the feeler rollers Is.

Shifting of the carriage 3B in response to reciprocal movement of theguide shaft is in turn employed to operate a control valve 43 by whichswivelling of the guide roll 1 by the actuating cylinder 9 iscontrolled. The control valve is mounted on the base 29 within thecarriage 30 and for sensitivity preferably has the lands 44 of itspiston 45 so arranged relative to the several inlets and outlets thatthe components of the fluid pressure, axially of the piston, are inbalance throughout movement of the piston in the valve body 46.Additionally, due to the lost motion between the cam plate 22 and thecarriage 30 permitted by the elongation of the end portions 31 of thecam slot 36, it is possible to hold the spacing between the lands 44 toa minimum, enabling the relatively slight movement of the cam pin withinthe central portion 38 of the cam slot to apply the force by which thepiston is moved to either terminal position.

In the form shown, the control valve 43 has an entrance port 4'! and ableed or exhaust port 48, which are selectively connectable by a pair ofconduits 49 to opposite ends of the actuating cylinder 9' throughcorresponding outlet ports 50 in the valve body 46, these conduitsserving either to charge or to bleed their respective ends of theactuating cylinder, depending upon the position of the piston 45. Notonly does the illustrated valve lend itself to quick-opening, but theextent of the opening of each of its outlet ports 50 and thereby thepressure applied at the ends of the actuating cylinder, are individuallyadjustable by stop nuts 5|, one threadedly engaging each end of thepiston 45, exteriorly of the valve body 45.

While theaforementioned lost motion connection between the cam plate 2'2and the carriage 30 permits the piston 45 to be connected directly tothe carriage, it has been found preferable to employ a yieldableconnection by spring loading the valve so that the force of the carriageis cushioned as it is transmitted to the control valve 43. This isaccomplished by attaching to either end of the piston 45 a stem orextension 52, each of sufficient length to extend through an aperture 53in the adjacent of the end plates 3| and be slidably received therein bya self-lubricating bushing 54 held by a retainer 55. Both stems arethreaded over their inner end portions to receive adjusting nuts 56 andare encircled between these nuts and the confronting walls of thecorresponding end plates 3! by coil springs 51, adjustment of the nuts,by controlling the precompression of the springs, determining theirresiliency and thus the extent to which they cushion the impact of thecarriage 39 on the control valve. Since, as one end plate of thecarriage moves toward the control valve, the other end plate moves away,the spring under load is enabled to transmit the force applied to itwithout resistance from the opposite spring, the latter being relievedof pressure as the former is loaded.

The inter-action of the control valve 43 and the actuating cylinder 9can best be understood by reference to the schematic view of Figure 8.As there shown, pressure is applied through the entrance port 41 of thecontrol valve and, in the illustrated position of the piston 45, isdirected through the right-hand of the outlet ports 50 into the closedend of the actuating cylinder 9, moving the actuating piston 58 towardsthe opposite ends of the cylinder. During this movement, back pressureis eliminated by venting the fluid behind the actuating piston 58through the other of the conduits 49 to the bleed port 48. In theillustration, the stop nut 5| abutting the the .stop nuts a sence endiDf the valve body =46 ihas beenaadjusted to ed without adjustment ofthe pressure in the fluid line. .A corresponding adjustment can, of

course, be -made for the reverse action of the actuating piston 58 by"turning in the other of To enable the desired ad justment of the stopnuts ti and the adjusting 'nuts "56 to be maintained, both are providedwith set screws -59 by which they are ilockable,

respectively, to the piston 45 and stems 52.

In operation, the feeler rollers 13 are vSQt -'on the guide shaft [5either in contact with or spaced from the edges of'the belt 2, dependingon .the extent of tracking to be permitted before restoring force isapplied toithe belt. With therollers so set, creepage of the belt towardeither side out of its normal travel, Will apply lateral pressureagainst one of the'feeler rollers and, therethroughcausethe guide shaft[5 to shift correspondingly transversely of'the beit. As the shaft I5starts to move, carrying with :it the cam plate 22, the cam pin 39 isdislodged from its position centrally of the cam slot '36 and movestowards one-of' the elongated end portions 31. In somoving the cam. pincauses the carriage til to shift relative to the control valve 13,loading one of the springs 5'! and shifting the piston 45correspondingly.

Assuming the movement of the belt to have been in the directionindicated by the position of the control piston 45 in Figure 8, forwhich the belt 2 would have tracked toward the left side of the guiderollof Figure 1, the actuating cylinder 9 immediately begins toswivel'the guide roll clockwise about the center pin is, enabling theguide roll to drive the belt back to normal alignment. Since the lostmotion between the cam pin 39and the camslot 3t oceursafterpressure hasbeen applied to the actuating cylinder and not before through excessivespacing of the lands of the piston of the control valve, as would. benecessary were the guide shaft connected directly to the .piston of thevalve,'a-.maximum-1'estoring force is obtained almost immediately on thestart of creepage. The belt guide .of the present invention isthusenabled to hold-creepage at aminimum, as Well as to prevent over-.driving of the belt by the guide roll, adapting it especially .forguiding .belts over short unsup ported spans where the delayed action ofthe usual beltguide is a definite handicap.

.From theabove detailed description it will be apparent that there hasbeen provided an improved guide for beltsand the like which isrex-.tremely sensitive to .creepage and, while enabled to apply .maximumrestoring force to a belt on slight creepage, is adapted to absorb thelimits ofthe creepage without-Causing binding "of the belt. It should beunderstood that the described and disclosed embodiment is :merelyexemplary 1 valve on displacement :of said :feeler .means by .said belt,and actuating means controlled by said control valve i-ior :swivelingsaid .guideroll to counter the direction of creepage rof 'said belt,said connecting means 'including :lost motion means :for absorbing:further creepage of said belt without aafiec'ting qcperation -1of :saidcontrol "valve.

2. A "belt .=guide comprising a :swivelable guide roll "for engaging andguiding a belt, feeler vmeans'"engageable with said 'belt anddisplaceable thereby on creeping thereof, a 'control valve, a lostmotion connection between said feeler means and control valve fortactuating'said. valve :on displacement fof s'aid feeler means whileabsorbing ffurther :displacemen't'thereof without interference with saidvalve, and fluid pressure 'means controlledbyrsaid control'valve forswiveling saidgui'de .roll in a direction to drive said belt back "tonormal position.

3. .A belt guide rcomprising fa guide llOll engageable with "a belt,means for swinging said guide 1011 about an :axis normal to said belt.feeler'means engageable withsaid belt and displatceable thereby on:creeping thereof, a control valve, :a lost motion-connection betweensaid 'feeler meanszandcontrol valve foractuating said valve :ondisplacement :of :said feeler means and absorbing further displacementof said feeler 'rneans withoutafiecting actuation of :said controlvalve, said control valve 'controlling'swinging of said rguideiroll by'said swinging'means: for driving .said belt-back to normal position.

4. A belt "guide .comprising a swivelable guide rollforengagingand-guiding a belt, feeler means engageable with saidbelt-and 'displaceable there by aonicreeping thereof, a control valve, apinand slot "cam connection between said control valve and feeler meansfor actuating said valve in response to displacement of said feelermeans, and fluid pressure means controlled by said control valve forswiveling said guide roll to restore said belt to normal position.

5. A belt guide comprising a swivelabl'e guide rollfor engaging-andguidinga belt, feeler means engageable withzsaid :belt and-displaceablethereby 1on creeping thereof, a member 'displaceable withssaidfeeler'means and having a cam slot, a cam pin 'ridablefinssa'id 'camslot, a control valve connected to said carn pin and operabletherethroughinresponseito displacement of said feeler means, and fluidpressure means controlled by --sai'd valv ffor :swiveling'said guide.roll in a direction 'to restore said .belttonormal position.

6. .A .rbelt :guide "comprising a 'swivelable guide 'rollfor'engagingand guiding abelt,ffeeler means :engageable withzsaid beltand displaceable thereby :on creeping thereof, a :member disp'laceablewith feeler means and having a 'camslot, a cam pin ridable insaidnamslot, a control valve yield- ..ab'ly connected to said :carn pin andoperable 'therethroug h :in resp'onse to displacementof said feelermeansgand fiuidpressure 'mean's controlleoi by said valve for swivelingsaid-guid roll in a direction to restore said belt to normal position.

7.1K belt guide ccmpfising a swivelable guide roll for engaging andguiding a belt, feeler means engageablew ith said b'elt anddisp'laceable thereby on oreeping thereof, a member displaceable withfeel'er means and having a cam slot, a cam pin ri'dabl'e in said camslot, a control valve, cushioning means interposed between andconnecting-said control valveand cam pin for operating said valve inresponse to displacement of feeler means, and fluid pressure meanscontrolled by said valve for swiveling said guide roll in a direction torestore said belt to normal position.

8. A belt guide comprising a swivelable guide roll for engaging andguiding a belt, a guide shaft spaced from said guide roll andreciprocable transversely of said belt, a pair of spaced feelers mountedon said shaft and disposed to engage opposite edges of said belt, acontrol valve, a lost motion connection between said control valve andshaft for operating said valve in response to displacement of saidfeelers by creeping of said belt, and actuating means controlled by saidcontrol valve for swiveling said guide roll to restore said belt tonormal position.

9. A belt guid comprising a swivelable guide roll for engaging andguiding a belt, a guide shaft spaced from said guide roll andreciprocable transversely of said belt, a pair of spaced feeler rollersmounted on said shaft and disposed to engage opposide edges of saidbelt, a control valve, a lost motion connection between said controlvalve and shaft for operating said valve in response to displacement ofsaid feeler rollers by creeping of said belt, and actuating meanscontrolled by said control valve for swiveling said guide roll torestore said belt to normal position.

10. A belt guide comprising a swivelable guide roll for engaging andguiding a belt, a guide shalt spaced from said guide roll andreciprocable transversely of said belt, a pair of feeler rollers carriedby said guide shaft and disposed to engage opposite edges of said belt,a control valve, cam means connecting said valve and shaft for operatingsaid valve in response to displacement of said feeler rollers bycreeping of said belt, lost motion means associated with said cam meansfor absorbing additional creepag of said belt, and actuating meanscontrolled by said valve for swiveling said guide roll to restore saidbelt to normal position. Y

11. A belt guide comprising a swivelable guide roll for engaging andguiding a belt, a pair of feeler rollers associated with said roll anddisposed to be engaged and displaced by opposite edges of said belt oncreeping thereof, a control valve, a lost motion connection between saidcontrol valve and feeler rollers for operating said valve in response todisplacement of said feeler rollers by creeping of said belt, andactuating means controlled by said control valve for swiveling saidguide roll and restoring said belt to normal position.

12. A belt guide comprising a swivelable guide roll for engaging andguiding a belt, a pair or feeler rollers associated with said guide rolland disposed to be engaged and displaced by opposite edges of said belt,a cam member displaceable with either of said feeler rollers and havinga cam slot elongated at either end, a cam pin ridable in said slot, acarriage mounting said pin and shiftable therewith transversely of saidslot on displacement of said cam member, a control valve operativelyconnected to said carriage and operated on shifting thereof, and anactuating cylinder controlled by said control valve for swiveling saidguide roll to restore said belt to normal position.

13. A belt guide comprising a swivelable guide roll for engaging andguiding a belt, a pair of feeler rollers associated with said guide rolland disposed to be engaged and displaced by opposite edges of said belt,a cam member displaceable with either of said feeler rollers and havinga cam slot elongated at either end, a cam pin ridable in said slot, acarriage mounting said pin and shiftabl therewith transversely of saidslot on displacement of said cam member, a control valve, yieldablemeans operatively connecting said control valve to said carriage foroperating said carriage in response to displacement of said feelerrollers, and an actuating cylinder controlled by said control valve forswiveling said guide roll to restore said belt to normal position.

14. A belt guide comprising a swivelable guide roll for engaging andguiding a belt, a pair of feeler rollers associated with said guide rolland disposed to be engaged and displaced by opposite edges of said belt,a cam member displaceable with either of said feeler rollers and havinga cam slot elongated at either end, a cam pin ridable in said slot, acarriage mounting said pin and shiftable therewith transversely of saidslot on displacement of said cam member, a control valve, adjustableyieldable means operatively connecting said control valve to saidcarriage for operating said carriage in response to displacement of saidfeeler rollers, and an actuating cylinder controlled by said controlvalve for swiveling said guide roll to restore said belt to normalposition.

15. A belt guide comprising a shiftable guide roll for engaging andguiding a belt, feeler means engageable with said belt and displaceablethereby on creeping thereof, a shiftable carriage, a pin and slotconnection between said feeler means and carriage, control meansoperatively connected to said carriage and operated by shifting thereofin response to displacement of said feeler means, and actuating meanscontrolled by said control means for shifting said guide roll to restoresaid belt to normal position.

16. A belt guide comprising a shiftable guide roll for engaging andguiding a belt, a guide shaft spaced from said guide roll andreciprocable transversely of said belt, a pair of spaced feelers carriedby said guide shaft and straddling said belt, said feelers andtherethrough said guide shaft being displaceable by said belt oncreeping thereof, a shiftable carriage, a pin and slot connectionbetween said carriage and shaft for shifting said carriage in responseto displacement of said feelers, control means operated by shifting ofsaid carriage, and actuating means controlled by said control means forshifting said guide roll to restore said belt to normal position.

1'7. A belt guide comprising a shiftable guide roll for engaging andguiding a belt, a guide shaft spaced from said guide roll andreciprocable transversely of said belt, a pair of spaced feelers carriedby said guide shaft and straddling said belt, said feelers and shaftbeing displaceable by said belt on creeping thereof, a shiftablecarriage, cam means connecting said carriage and shaft for shifting saidcarriage, control means operated by shifting of said carriage, andactuating means controlled by said control means for shifting said guideroll to restore said belt to normal position.

Name Date 1,545,309 Davis et a1. July 7, 1925 2,488,294 Hornbostel Nov.15, 1949

